Ventilation grill for boats



FIG. 1 is a top plan view of a ventilation grill for boats, showing my new design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is an end view of the ventilation grill as seen from the left end in FIG. 2; and

FIG. 5 is an end view of the ventilation grill as seen from the right end in FIG. 2. 

The ornamental design for a ventilation grill for boats, as shown. 